Land Preparation – plow the area once or two times followed by several harrowings to completely pulverize and expose the soil. It is best done during the dry season.
Stake the field and dig holes at a distance of 5 – 7 meters to accommodate 277 seedlings in a hectare. In fertile soils, wider spacing is desirable.
Planting – the planting materials are transplanted into the holes earlier prepared after pruning some of the leaves and removing the plants from the containers. The plants are aligned with other trees in all directions. The best time to plant is at the onset or during the rainy season. Weeding/cultivation ? shallow cultivation around the base of the plant is recommended to prevent root injury, incorporate organic matter into the soil and to control weeds especially when trees need all the available soil moisture.
Pruning – pruning is a must in guava production. This is done if a certain form is desired like growing the tree with a spreading or symmetrical or limited crown or to keep number of branches. However, when the trees have established a strong framework and started to bear fruit, little training is required. The root sprouts; low-lying branches, disease infected and other dead branches, which are unnecessary just, have to be eliminated.
Fertilization – guava trees should be kept healthy through application of fertilizers from the time they are planted until they continue to produce fruits.
In the absence of definite information regarding the fertilizer requirements of guava in the Philippines, it is about 100-500 g ammonium sulfate will be applied around the base of each tree twice a year. The fertilizer will be applied one month after planting and 6 months after or towards the end of the rainy season. The amount will be increased, as the tree grows bigger. At the start of fruiting, each tree should be given about 300 – 500 g complete fertilizer, preferably one containing more nitrogen and potassium per application. At the peak of production (about 10 -18 years, an annual application of 2 kg or more complete fertilizer per tree, split in application may be required to sustain growth development and production of fruits.
Irrigation – no irrigation is required when trees are planted during the rainy season. But in case of prolonged dry weather, the orchard should be irrigated every 10 days or as often as maybe necessary. Irrigation when applied during fruit development can increase production through fruit size.
Intercropping – while the guava trees are not yet fully productive, intercropping of short season crops like vegetables, leguminous crops, root crops and other annual crops can be done. Aside from added income it will also prevent the growth of weeds and help cultivate the land in the orchard. However, this intercrop should be removed once the main crop becomes too crowded.
Control of Insect Pests and Diseases
Oriental fruit fly (Daucus dorsalis Hendel). The larvae burrow through the ripe fruits making them unfit for human consumption.
Control: Bagging the fruit. To avoid infestation, harvest fruit at the earliest possible time. Collect the infested fruits into a kerosene can with a thin layer of sand at the bottom and destroy the larva/pupa by heat
Aphids (Aphis gosypii Glover) – the pest damage the plant by feeding on young growth causing the curling of leaves.
Control: Spray with appropriate insecticide (like malathion) when necessary. Aphids are fed upon by lady beetles and by maggot of syrphid flies. They also parasitized by minute parasitic hymenopterans.
Mealy Bugs and Scale Insects:
Common White Mealy Bug (Planococcus lilacinus Ckll). It attacks and draws plant sap from the young shoots and fruits of guava. Its actual damage is economically insignificant, however, the ants that it attracts are nuisance when picking the fruits.
Control: Seldom needs remedial measures
Green Scale Insects (Coccus viridis Green). It is a soft scale that infests the young shoots, mostly on leaves. It is oval in shape, about 2 mm long, foliage green in color with an irregular V-shaped black on its back.
Control: Use of entomogenous fungi effective especially during rainy season. Use of small wash parasite, Coccophagus tibialis
Moth (Zuezera coffeae Nietn). Its pink caterpillar bores into young upright growing stems tunneling the stem center where it feeds and develops; extruding stem may suddenly die or break off at the level of the exit hole.
Control: If discovered early enough, the infested stem may be saved by inserting a coconut leaf midrib into the tunnel and pushing it in as far as it would go to speak and kill the caterpillar inside. If infested twigs has broken off spear the larva; dead infested twigs that have not broken off should be broken and the larva on pupa speared.
Spotting of leaves and fruits ? caused by the parasitic alga, Cepaleuros mycoides Darst., is rather severe on some types and varieties in humid areas.
Control: Spraying with a Copper Fungicide
Anthracnose or Cracker – caused by Gloeasprrium psidii G. Del. The fungus produces two kinds of symptoms. Formation of cankerous spots throughout the fruit surface. These cankers are circular, dry and raised. In some areas, however, infected fruits becomes undersized misshaped, hard and dry.
Typical sunken soft lesions usually produced by anthracnose can be observed on ripe fruits. Under moist conditions, pinkish masses of spores can be seen on lesions surface. It also causes dieback of plants. On the leaves, the disease produces angular, rusty brown spots of varying sizes, usually 2-5 mm in diameter. During the rainy season, the blight of shoots is a common symptom.
Control: No control measure has ever been recommended although spray of fungicides can be recommended.
Wilting – caused by Gloremella psidii Sheld is another disease known to attack guava. The disease causes mummification and blackening of immature fruits.
For further information, contact:
Paseo de Valmayor, Los Banos, Laguna
Telephone No.: (049) 5360014 to 20
Manila Liaison Office:
DOST Complex, Gen. Santos Ave., Bicutan, Taguig City
Tel.: 8372071 to 82 loc 2420
E-mail: [email protected], [email protected]